1. Field Of The Invention
The invention relates to a method for powering electronic circuits equipped with solar cells, and an apparatus for accomplishing the method. The invention also relates to use of a power supply system for electronic circuits equipped with solar cells.
2. Description of the Prior Art
Electrical and electronic devices which operate independently of power mains, some of which devices are equipped with digital displays, have long been known. As a rule, their circuits and displays (with modern displays ordinarily being of the liquid crystal type) are supplied with voltage and current even today by batteries of the standard or storage type. Batteries are particularly used where reliable means of powering the circuits and/or displays must be furnished which operate without interruption over a relatively long period, and possibly under unfavorable light conditions. Accordingly, devices powered by solar cells, particularly measuring devices powered by solar cells, have been little used. Current knowledge holds that batteries present an environmental hazard, particularly when disposed of incorrectly. In applications where solar cells are successfully employed, as a rule the circuits supplied have low power demand and are only required to function under conditions where a certain minimum level of illumination is present. In the event of darkness, the information in these circuits is lost and the displays disappear. In applications where there are periods of interruption of illumination during which operation must continue, storage batteries are provided which the solar cells serve to charge and which in turn provide the power for the circuits and/or displays. An inherent disadvantage of such apparatus is that under conditions of extended interruption in operation or extended darkness, the storage batteries discharge, and as a rule they require several hours to recharge, thereby making the devices unavailable during a fairly long period at the start of the charging cycle.